Make "rev-tree" able to read its own output again from the cache.
[git/git.git] / checkout-cache.c
CommitLineData
33db5f4d
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1/*
2 * Check-out files from the "current cache directory"
3 *
4 * Copyright (C) 2005 Linus Torvalds
5 *
6 * Careful: order of argument flags does matter. For example,
7 *
8 * checkout-cache -a -f file.c
9 *
10 * Will first check out all files listed in the cache (but not
11 * overwrite any old ones), and then force-checkout "file.c" a
12 * second time (ie that one _will_ overwrite any old contents
13 * with the same filename).
14 *
15 * Also, just doing "checkout-cache" does nothing. You probably
16 * meant "checkout-cache -a". And if you want to force it, you
17 * want "checkout-cache -f -a".
18 *
19 * Intuitiveness is not the goal here. Repeatability is. The
20 * reason for the "no arguments means no work" thing is that
21 * from scripts you are supposed to be able to do things like
22 *
23 * find . -name '*.h' -print0 | xargs -0 checkout-cache -f --
24 *
25 * which will force all existing *.h files to be replaced with
26 * their cached copies. If an empty command line implied "all",
27 * then this would force-refresh everything in the cache, which
28 * was not the point.
29 *
30 * Oh, and the "--" is just a good idea when you know the rest
31 * will be filenames. Just so that you wouldn't have a filename
32 * of "-a" causing problems (not possible in the above example,
33 * but get used to it in scripting!).
34 */
35#include "cache.h"
36
37static int force = 0, quiet = 0;
38
83adac3c
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39static void create_directories(const char *path)
40{
41 int len = strlen(path);
42 char *buf = malloc(len + 1);
43 const char *slash = path;
44
45 while ((slash = strchr(slash+1, '/')) != NULL) {
46 len = slash - path;
47 memcpy(buf, path, len);
48 buf[len] = 0;
cfd88e2b 49 mkdir(buf, 0755);
83adac3c
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50 }
51}
52
53static int create_file(const char *path, unsigned int mode)
54{
55 int fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, 0600);
56 if (fd < 0) {
57 if (errno == ENOENT) {
58 create_directories(path);
59 fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, 0600);
60 }
61 }
62 if (fd >= 0)
63 fchmod(fd, mode);
64 return fd;
65}
66
33db5f4d
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67static int write_entry(struct cache_entry *ce)
68{
69 int fd;
70 void *new;
71 unsigned long size;
72 long wrote;
8d3af1d5 73 char type[20];
33db5f4d 74
8d3af1d5
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75 new = read_sha1_file(ce->sha1, type, &size);
76 if (!new || strcmp(type, "blob")) {
f7391ce3 77 fprintf(stderr, "checkout-cache: unable to read sha1 file of %s (%s)\n",
33db5f4d
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78 ce->name, sha1_to_hex(ce->sha1));
79 return -1;
80 }
83adac3c 81 fd = create_file(ce->name, ce->st_mode);
33db5f4d 82 if (fd < 0) {
f7391ce3 83 fprintf(stderr, "checkout-cache: unable to create %s (%s)\n",
33db5f4d
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84 ce->name, strerror(errno));
85 free(new);
86 return -1;
87 }
88 wrote = write(fd, new, size);
89 close(fd);
90 free(new);
91 if (wrote == size)
92 return 0;
f7391ce3 93 fprintf(stderr, "checkout-cache: unable to write %s\n", ce->name);
33db5f4d
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94 return -1;
95}
96
97static int checkout_entry(struct cache_entry *ce)
98{
99 if (!force) {
100 struct stat st;
101
102 if (!stat(ce->name, &st)) {
103 unsigned changed = cache_match_stat(ce, &st);
f7391ce3
LT
104 if (changed && !quiet)
105 fprintf(stderr, "checkout-cache: %s already exists\n", ce->name);
106 return 0;
33db5f4d
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107 }
108 }
109 return write_entry(ce);
110}
111
112static int checkout_file(const char *name)
113{
114 int pos = cache_name_pos(name, strlen(name));
115 if (pos < 0) {
116 if (!quiet)
f7391ce3 117 fprintf(stderr, "checkout-cache: %s is not in the cache\n", name);
33db5f4d
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118 return -1;
119 }
120 return checkout_entry(active_cache[pos]);
121}
122
123static int checkout_all(void)
124{
125 int i;
126
127 for (i = 0; i < active_nr ; i++) {
128 struct cache_entry *ce = active_cache[i];
129 if (checkout_entry(ce) < 0)
130 return -1;
131 }
132 return 0;
133}
134
135int main(int argc, char **argv)
136{
137 int i, force_filename = 0;
138
139 if (read_cache() < 0) {
f7391ce3 140 fprintf(stderr, "Invalid cache\n");
33db5f4d
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141 exit(1);
142 }
143
144 for (i = 1; i < argc; i++) {
145 const char *arg = argv[i];
146 if (!force_filename) {
147 if (!strcmp(arg, "-a")) {
148 checkout_all();
149 continue;
150 }
151 if (!strcmp(arg, "--")) {
152 force_filename = 1;
153 continue;
154 }
155 if (!strcmp(arg, "-f")) {
156 force = 1;
157 continue;
158 }
159 if (!strcmp(arg, "-q")) {
160 quiet = 1;
161 continue;
162 }
163 }
164 checkout_file(arg);
165 }
166 return 0;
167}